. "1N-(1-carbamoyl-2-hydroxypropyl)-15-[3-amino(imino)methylaminopropyl]-6-(1-amino-2-phenylethylcarboxamido)-18-(1-hydroxyethyl)-12-(1H-3-indolylmethyl)-9-(4-iodobenzyl)-2,2-dimethyl-7,10,13,16,19-pentaoxo-3,4-dithia-8,11,14,17,20-pentaazacycloicosane" . "20" . . . . .